Re: [PATCH] selftests:dma: Fix compile error in user-space tool

[Shuah Khan <skhan@linuxfoundation.org>]

On 1/9/23 11:07, Gerd Bayer wrote:
> Since [1] the user-space program dma_map_benchmark shares the header file
> linux/map_benchmark.h with the kernel driver in kernel/dma/map_benchmark.c.
> With latest kernel version this does not compile anymore.
> 
> While https://kernelnewbies.org/KernelHeaders suggests otherwise, allow it
> to use kernel headers through the uapi/ include directory. I assume we can
> do so safely, since the controlling user-space program is distributed with
> the kernel.
> 
> With this change dma_map_benchmark compiles with just the obvious warning
> about uapi usage on ARCH=x86, arm64, and s390 and runs on ARCH=s390.
> 
> [1] commit 8ddde07a3d28 ("dma-mapping: benchmark: extract a common header
> file for map_benchmark definition")
> 
> Signed-off-by: Gerd Bayer <gbayer@linux.ibm.com>
> Acked-by: Xiang Chen <chenxiang66@hisilicon.com>
> ---
>   tools/testing/selftests/dma/dma_map_benchmark.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/tools/testing/selftests/dma/dma_map_benchmark.c b/tools/testing/selftests/dma/dma_map_benchmark.c
> index 5c997f17fcbd..d49d7ea6a63e 100644
> --- a/tools/testing/selftests/dma/dma_map_benchmark.c
> +++ b/tools/testing/selftests/dma/dma_map_benchmark.c
> @@ -10,7 +10,7 @@
>   #include <unistd.h>
>   #include <sys/ioctl.h>
>   #include <sys/mman.h>
> -#include <linux/types.h>
> +#include <uapi/linux/types.h>
>   #include <linux/map_benchmark.h>
>   
>   #define NSEC_PER_MSEC	1000000L
> 
> base-commit: 1fe4fd6f5cad346e598593af36caeadc4f5d4fa9

On Linux 6.2-rc3, dma_map_benchmark compiles just fine. You do
have to do "make headers_install" first as kselftest depends
on headers being installed in the repo.

Please let me know if you are seeing compile problems even after
installing headers.

thanks,
-- Shuah